Re: [Elecraft] K3 dbV in 2.38

[Jim Brown]

On Thu, 18 Sep 2008 05:36:40 -0700 (PDT), alsopb wrote:

>First question.  What is meant by stable value of AFV?

>Here's what I see for a bunch of AFV edited values one after another with no
>change in K3 settings.
>1579,1688,1598,1624,1696,1613, 2168,1758,1425.
>The range is 6db.  

Sure. It's audio, and you're looking at the reading of a voltmeter looking at 
that audio. ANY voltmeter will have a varying reading on program audio (that 
is, music, someone talking, even band noise and QRN), because audio voltage 
varies with time over a range of 40-60 dB. Many audio voltmeters, including 
the one in the K3 that generates the AFV and dBV readings include an 
integration circuit that averages the voltage over a selected time period (1 
second or one half second in the K3). This integration drastically reduces 
the variation as someone talks or static crashes crash. That's why your 
readings vary by only 6 dB rather than 30-50 dB. As Eric and Lyle have 
observed, these voltmeters are designed for use with test signals that are 
constant (like a signal genertor). 

As noted, it's quite nice to have this function. The only thing wrong is 
improperly calling it dBV. dBV MEANS an AC voltage reading where 0dBV = 1 
volt RMS. dBm means 1 milliwatt in whatever impedance is being used. If you 
don't believe that, look at the manual for any HP product that generates or 
measures voltage. Voltages expressed in dB with respect to some reference are 
widely used in audio. Often, some reference voltage other than the standard 
(for example, the output of a generator, or the peak value of a system's 
response) can be selected as a reference, and all subsequent readings 
referenced to that voltage. In that scenario, the notation dBr is often used. 

I suggest that the log voltmeter (that is, reading in dB) begin with one of 
the international references, either 0.78V (0dBu) or 1 V (0dBV), and then 
change to dBr when some other reference has been selected. Now, you have an 
actual calibrated audio voltmeter, rather than only a relative voltage 
indicator. 

73,

Jim Brown K9YC
Audio Systems Group, Inc. 


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Re: [Elecraft] K3 dbV in 2.38

[Jack Smith]

I've independently measured the linear range of the DBV function as just 
over 60 dB, which is quite impressive. You can see the plot at

http://www.cliftonlaboratories.com/elecraft_k3_noise_blanker_and_crystal_dsp_filtering.htm.

That page also provides measured filter response curves using the K3's 
DBV function.


DBV is a very useful tool and a tip of the hat to the lads at Elecraft 
for including it. (lasses as well as lads, if appropriate.)


Jack K8ZOA
www.cliftonlaboratories.com



Eric Swartz WA6HHQ - Elecraft wrote:

Hi Brian,

The dBV and AFV functions were designed primarily for use with steady 
state lab signals to test receiver sensitivity etc. We added these two 
displays to speed our final test of the K3 in production, and as an 
aid to do this in the field with simple tools like our XG2 test 
oscillator. They were not intended for dynamic signal, off the air 
measurements.


73, Eric  WA6HHQ
---

_..._



alsopb wrote:
Apparently I need some help in trying to use this dBV capability with 
on the

air signals.

For example, using it as an AGC off "relative" S-meter with digital 
readout

to run some antenna pattern checks for skewness etc.

I've used it just fine in "lab type" measurements with a constant signal
source.

First question.  What is meant by stable value of AFV?

Here's what I see for a bunch of AFV edited values one after another 
with no

change in K3 settings.
1579,1688,1598,1624,1696,1613, 2168,1758,1425.
The range is 6db. 
Is the reference value of AFV used in the dbV calculation the last 
one taken
at the instant one leaves the menu entry?  Yes, it doesn't really 
matter if

that values is used forever.

Suppose one then takes a series of dbV measurements,  is the 
reference AFV

ever changed during the set of readings?

The integration times available are 500 and 1000 ms.  It would seem that
longer integration times are required for off air type measurements.

Is there any integration time in the measured voltage used in the dBV
calculation?  Or is it nearly an instantaneous value?  For off the 
air type

measurements, it would seem that a suitably long value is needed.

73 de Brian/K3KO
  

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Re: [Elecraft] K3 dbV in 2.38

[Eric Swartz WA6HHQ - Elecraft]

Hi Brian,

The dBV and AFV functions were designed primarily for use with steady 
state lab signals to test receiver sensitivity etc. We added these two 
displays to speed our final test of the K3 in production, and as an aid 
to do this in the field with simple tools like our XG2 test oscillator. 
They were not intended for dynamic signal, off the air measurements.


73, Eric  WA6HHQ
---

_..._



alsopb wrote:

Apparently I need some help in trying to use this dBV capability with on the
air signals.

For example, using it as an AGC off "relative" S-meter with digital readout
to run some antenna pattern checks for skewness etc.

I've used it just fine in "lab type" measurements with a constant signal
source.

First question.  What is meant by stable value of AFV?

Here's what I see for a bunch of AFV edited values one after another with no
change in K3 settings.
1579,1688,1598,1624,1696,1613, 2168,1758,1425.
The range is 6db.  


Is the reference value of AFV used in the dbV calculation the last one taken
at the instant one leaves the menu entry?  Yes, it doesn't really matter if
that values is used forever.

Suppose one then takes a series of dbV measurements,  is the reference AFV
ever changed during the set of readings?

The integration times available are 500 and 1000 ms.  It would seem that
longer integration times are required for off air type measurements.

Is there any integration time in the measured voltage used in the dBV
calculation?  Or is it nearly an instantaneous value?  For off the air type
measurements, it would seem that a suitably long value is needed.

73 de Brian/K3KO
  

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Re: [Elecraft] K3 dbV in 2.38

[Lyle Johnson]

I've used it just fine in "lab type" measurements with a constant signal
source.


Which is precisely what it was designed for.


Is the reference value of AFV used in the dbV calculation the last one taken
at the instant one leaves the menu entry?


It is the last one. It might be the last one DISPLAYED, or if it has 
started another measurement interval, then it will be the next one.



Suppose one then takes a series of dbV measurements,  is the reference AFV
ever changed during the set of readings?


No, the reference is only updated if you go back to AFV.


The integration times available are 500 and 1000 ms.


Correct.  These are the choices.


Is there any integration time in the measured voltage used in the dBV
calculation?


500 or 1000 ms, as noted above.

73,

Lyle KK7P

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Re: [Elecraft] K3 dbV in 2.38

[alsopb]

Apparently I need some help in trying to use this dBV capability with on the
air signals.

For example, using it as an AGC off "relative" S-meter with digital readout
to run some antenna pattern checks for skewness etc.

I've used it just fine in "lab type" measurements with a constant signal
source.

First question.  What is meant by stable value of AFV?

Here's what I see for a bunch of AFV edited values one after another with no
change in K3 settings.
1579,1688,1598,1624,1696,1613, 2168,1758,1425.
The range is 6db.  

Is the reference value of AFV used in the dbV calculation the last one taken
at the instant one leaves the menu entry?  Yes, it doesn't really matter if
that values is used forever.

Suppose one then takes a series of dbV measurements,  is the reference AFV
ever changed during the set of readings?

The integration times available are 500 and 1000 ms.  It would seem that
longer integration times are required for off air type measurements.

Is there any integration time in the measured voltage used in the dBV
calculation?  Or is it nearly an instantaneous value?  For off the air type
measurements, it would seem that a suitably long value is needed.

73 de Brian/K3KO
-- 
View this message in context: 
http://n2.nabble.com/K3-dbV-in-2.38-tp1092599p1098058.html
Sent from the Elecraft mailing list archive at Nabble.com.

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Re: [Elecraft] K3 dbV in 2.38

[Alan Bloom]

> Into a linear load, and I presume we have one here[A], there is no 
> difference between dB relative to a voltage, using the 20 log10, 
> voltage, formula and dB relative to the power corresponding to that 
> voltage using the 10 log10. power, formula.

That's only true if the source and load impedance are equal.  For
example, if an amplifier has a high-impedance input and a near-zero-ohm
output, then the power gain (in dB) is almost infinite even if the
voltage gain (in dB) is small.

That's probably why Elecraft chose the dBV notation to mean "deciBels of
voltage gain" even though it might be confused with the official
meaning, "deciBels relative to 1.0 volt".

Al N1AL


On Wed, 2008-09-17 at 00:03, David Woolley (E.L) wrote:
> Lyle Johnson wrote:
> 
> > 
> > We have a total of three characters available, and we wanted to express 
> > that this was a dB value, and it was voltage based.  So we used dBV.
> 
> Into a linear load, and I presume we have one here[A], there is no 
> difference between dB relative to a voltage, using the 20 log10, 
> voltage, formula and dB relative to the power corresponding to that 
> voltage using the 10 log10. power, formula.  The difference between 10 
> and 20 is to account for the need to square the voltage to get the power.
> 
> In this case the units should be bare dB.  You will still have problems 
> because of the large number of people who don't know the definition of a 
> dB and are only used to seeing dB's relative to some defined standard.
> 
> 
> [A] strictly speaking the load at any one stage could be non-linear, as 
> long as the total system, through to the air outside the speaker 
> believes in a linear way.

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Re: [Elecraft] K3 dbV in 2.38

[Don Wilhelm]

You should be able to use the AFV readings instead of the voltage 
measured with a DMM across the speaker - then using those values, enter 
them into the calculations in the XG2 manual for calculating MDS.


73,
Don W3FPR

Björn Mohr wrote:

On 2008-09-17 00.26, "Lyle Johnson" <[EMAIL PROTECTED]> wrote:

  

The K3's dBV function is a *relative* measure.  It must be set to
whatever reference you wish by first using AFV.  The calculation
measurement is true RMS.  It is used for measuring things like MDS, AGC
slope, roofing filter attenuation and so forth.



So what's the correct procedure for measuring MDS using the internal meter
and a XG2 oscillator?

73 de Björn /SM0MDG




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Re: [Elecraft] K3 dbV in 2.38

[Lyle Johnson]

The K3's dBV function is a *relative* measure.  It must be set to
whatever reference you wish by first using AFV.  The calculation
measurement is true RMS.  It is used for measuring things like MDS, AGC
slope, roofing filter attenuation and so forth.


So what's the correct procedure for measuring MDS using the internal meter
and a XG2 oscillator?


See the MDS procedure in the XG2 manual, pages 5-7.  You can use the K3 
AFV and/or dBV functions instead of an external meter.


73,

Lyle KK7P

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Re: [Elecraft] K3 dbV in 2.38

[Björn Mohr]

On 2008-09-17 00.26, "Lyle Johnson" <[EMAIL PROTECTED]> wrote:

> The K3's dBV function is a *relative* measure.  It must be set to
> whatever reference you wish by first using AFV.  The calculation
> measurement is true RMS.  It is used for measuring things like MDS, AGC
> slope, roofing filter attenuation and so forth.

So what's the correct procedure for measuring MDS using the internal meter
and a XG2 oscillator?

73 de Björn /SM0MDG




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Re: Re: [Elecraft] K3 dbV in 2.38

[d.cutter]

Lateral thinking.  Sounds good to me
David
G3UNA

> 
> From: "Geoffrey Mackenzie-Kennedy" <[EMAIL PROTECTED]>
> Date: 2008/09/17 Wed AM 09:33:31 BST
> To: "Elecraft Discussion List" 
> Subject: Re: [Elecraft] K3 dbV in 2.38
> 
> Would it be useful to call it Vdb,  i.e. a voltage measurement not 
> necessarily using the 1V RMS standard reference?
>  
> 73,
> Geoff
> GM4ESD
>  
>  
> > On Tue, 16 Sep 2008 15:40:04 -0700, Lyle Johnson wrote:
> >
> >>> Maybe dBv stands for dB "variable," not dB with respect to a volt.
> >
> >>Not with respect one volt, but voltage based, using the 20log rather
> >>than the power-based 10log conversion.
>  
> Jim K9YC wrote:
> 
> > Hold on a minute. We cannot sit over in our little corner and pretend
> > that the rest of the world does not exist. That's how we got into
> > trouble with the KIO3.
> >
> > dBV is a voltage measure with a reference of 1V RMS. It's an
> > international standard. If a K3 function does something else, it needs
> > to be called something else.
> 
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Re: [Elecraft] K3 dbV in 2.38

[Geoffrey Mackenzie-Kennedy]

Would it be useful to call it Vdb,  i.e. a voltage measurement not 
necessarily using the 1V RMS standard reference?


73,
Geoff
GM4ESD



On Tue, 16 Sep 2008 15:40:04 -0700, Lyle Johnson wrote:


Maybe dBv stands for dB "variable," not dB with respect to a volt.



Not with respect one volt, but voltage based, using the 20log rather
than the power-based 10log conversion.


Jim K9YC wrote:


Hold on a minute. We cannot sit over in our little corner and pretend
that the rest of the world does not exist. That's how we got into
trouble with the KIO3.

dBV is a voltage measure with a reference of 1V RMS. It's an
international standard. If a K3 function does something else, it needs
to be called something else.


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Re: [Elecraft] K3 dbV in 2.38

[David Woolley (E.L)]

Lyle Johnson wrote:



We have a total of three characters available, and we wanted to express 
that this was a dB value, and it was voltage based.  So we used dBV.


Into a linear load, and I presume we have one here[A], there is no 
difference between dB relative to a voltage, using the 20 log10, 
voltage, formula and dB relative to the power corresponding to that 
voltage using the 10 log10. power, formula.  The difference between 10 
and 20 is to account for the need to square the voltage to get the power.


In this case the units should be bare dB.  You will still have problems 
because of the large number of people who don't know the definition of a 
dB and are only used to seeing dB's relative to some defined standard.



[A] strictly speaking the load at any one stage could be non-linear, as 
long as the total system, through to the air outside the speaker 
believes in a linear way.

--
David Woolley
"The Elecraft list is a forum for the discussion of topics related to 
Elecraft products and more general topics related ham radio"

List Guidelines 
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Re: [Elecraft] K3 dbV in 2.38

[Lyle Johnson]

If you reference to a full scale meter reading or A/D converter clipping 
level, a standard that is in use is dBFS (or dBfs).


We have a total of three characters available, and we wanted to express 
that this was a dB value, and it was voltage based.  So we used dBV.


73,

Lyle KK7P

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Re: [Elecraft] K3 dbV in 2.38

[Kok Chen]

On Sep 16, 2008, at 5:38 PM, Joe Subich, W4TV wrote:


I suppose when Wayne has time, he can modify the display
driver to light two fewer segments so the "V" is "v."


That is probably no good either.

dBv is the deprecated version of dBu.  It was changed from dBv to dBu  
because it was too easy to confuse dBv with dBV.


If you reference to a full scale meter reading or A/D converter  
clipping level, a standard that is in use is dBFS (or dBfs).


73
Chen, W7AY


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RE: [Elecraft] K3 dbV in 2.38

[Joe Subich, W4TV]

I suppose when Wayne has time, he can modify the display 
driver to light two fewer segments so the "V" is "v."  
That will not conflict with dBV is that offends your sense 
of propriety. 

However, since the previous "meter selection" is AFV (AF Voltage), 
dBV makes plenty of sense as way to identify the meter setting. 
dBA would also make sense but it also has a specific "standard" 
meaning. 


 

> -Original Message-
> From: [EMAIL PROTECTED] 
> [mailto:[EMAIL PROTECTED] On Behalf Of Jim Brown
> Sent: Tuesday, September 16, 2008 7:54 PM
> To: elecraft@mailman.qth.net
> Subject: Re: [Elecraft] K3 dbV in 2.38
> 
> 
> On Tue, 16 Sep 2008 15:40:04 -0700, Lyle Johnson wrote:
> 
> >> Maybe dBv stands for dB "variable," not dB with respect to a volt.
> 
> >Not with respect one volt, but voltage based, using the 20log rather
> >than the power-based 10log conversion.
> 
> Hold on a minute. We cannot sit over in our little corner and pretend 
> that the rest of the world does not exist. That's how we got into 
> trouble with the KIO3. 
> 
> dBV is a voltage measure with a reference of 1V RMS. It's an 
> international standard. If a K3 function does something else, 
> it needs 
> to be called something else. 
> 
> 73,
> 
> Jim K9YC
> 
> 
> 
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Re: [Elecraft] K3 dbV in 2.38

[Kok Chen]

On Sep 16, 2008, at 5:07 PM, Augie Hansen wrote:

Jim Brown wrote:

...
Hold on a minute. We cannot sit over in our little corner and  
pretend that the rest of the world does not exist. That's how we  
got into trouble with the KIO3.
dBV is a voltage measure with a reference of 1V RMS. It's an  
international standard. If a K3 function does something else, it  
needs to be called something else.


Agreed. If dBr is not already taken how about using it to mean "dB  
relative"? My searches have turned up no conflicts for this  
designation as it relates to voltage measurements.


I agree with both of you.

However, just a small nit...

dB (decibel) is already a relative measure, with no units.

When another letter is appended, it turns the value to an absolute  
measure (m for miiliwatts, V for 1 V RMS, u for 0.775 V RMS, etc).  If  
you use dBr, you'll need to define what unit "r" is in.  I.e., dBr is  
no longer just a ratio, but a value that is relative to 1 "r".


73
Chen, W7AY

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Re: [Elecraft] K3 dbV in 2.38

[Augie Hansen]

Jim Brown wrote:

...
Hold on a minute. We cannot sit over in our little corner and pretend 
that the rest of the world does not exist. That's how we got into 
trouble with the KIO3. 

dBV is a voltage measure with a reference of 1V RMS. It's an 
international standard. If a K3 function does something else, it needs 
to be called something else. 


Agreed. If dBr is not already taken how about using it to mean "dB 
relative"? My searches have turned up no conflicts for this designation 
as it relates to voltage measurements.


Gus Hansen
KB0YH

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Re: [Elecraft] K3 dbV in 2.38

[Jim Brown]

On Tue, 16 Sep 2008 15:40:04 -0700, Lyle Johnson wrote:

>> Maybe dBv stands for dB "variable," not dB with respect to a volt.

>Not with respect one volt, but voltage based, using the 20log rather 
>than the power-based 10log conversion.

Hold on a minute. We cannot sit over in our little corner and pretend 
that the rest of the world does not exist. That's how we got into 
trouble with the KIO3. 

dBV is a voltage measure with a reference of 1V RMS. It's an 
international standard. If a K3 function does something else, it needs 
to be called something else. 

73,

Jim K9YC



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Re: [Elecraft] K3 dbV in 2.38

[Lyle Johnson]

Maybe dBv stands for dB "variable," not dB with respect to a volt.


Not with respect one volt, but voltage based, using the 20log rather 
than the power-based 10log conversion.


AFV is "AF Voltage" and corresponds to the voltage you would measure 
across the speaker with AF GAIN set to max.  Units are mV RMS, and 
over-range truncates the MSD in the display (but is still accurate, I 
think, over the serial port).


I no longer remember if this is with AF gain scaling set to H or L.

73,

Lyle KK7P

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Re: [Elecraft] K3 dbV in 2.38

[Jack Smith]

Maybe dBv stands for dB "variable," not dB with respect to a volt.

Once you get used to it, the relative reference can be of some benefit. 
For example, set dBV to 0.0 at the bandwith peak and then the dBV 
reading gives you a direct reference to how many dB down from the filter 
peak you are when doing a filter bandwidth scan.


Jack K8ZOA


Jim Brown wrote:

On Tue, 16 Sep 2008 17:29:46 -0400, Joe Subich, W4TV wrote:

  
As Stef says, you must first set a reference (AFV) before the 
dBV (relative change) value has any meaning. 



That MAY be how it's programmed, but that would not be right. 0 dBV 
is quite well defined by international standard as 1 volt RMS. 0 dBu 
is defined as 0.78 volts. Both of these are purely voltage 
measurements, independent of impedance. 0 dBm is 1 mw -- to measure 
it, one must also know the impedance. 0 dBu is the voltage that 
would be present with 0 dBm in 600 ohms. 


73,

Jim K9YC



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Re: [Elecraft] K3 dbV in 2.38

[Lyle Johnson]

The K3's dBV function is a *relative* measure.  It must be set to 
whatever reference you wish by first using AFV.  The calculation 
measurement is true RMS.  It is used for measuring things like MDS, AGC 
slope, roofing filter attenuation and so forth.


This function has been in the K3 for a very long time (as K3 things go) 
and has always worked in exactly this manner.


73,

Lyl eKK7P

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RE: [Elecraft] K3 dbV in 2.38

[Jim Brown]

On Tue, 16 Sep 2008 17:29:46 -0400, Joe Subich, W4TV wrote:

>As Stef says, you must first set a reference (AFV) before the 
>dBV (relative change) value has any meaning. 

That MAY be how it's programmed, but that would not be right. 0 dBV 
is quite well defined by international standard as 1 volt RMS. 0 dBu 
is defined as 0.78 volts. Both of these are purely voltage 
measurements, independent of impedance. 0 dBm is 1 mw -- to measure 
it, one must also know the impedance. 0 dBu is the voltage that 
would be present with 0 dBm in 600 ohms. 

73,

Jim K9YC



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RE: [Elecraft] K3 dbV in 2.38

[Joe Subich, W4TV]

> Try this.  Set your K3 up to display dBV.  Turn your K3 off.  
> Turn the K3 on.  Look at the value.  Wait.  See if it ever 
> changes from +99.9.  It never does here.

In setting up the dBV display, you must first set a reference. 
Select AFV (AF Voltage), allow the display to stabilize, then 
select dBV.  

If dBV is selected when initially applying power to the K3, the 
reference voltage is ALWAYS zero volts.  ANY audio output is an 
infinite increase over zero - thus 99.9 dBV.  

As Stef says, you must first set a reference (AFV) before the 
dBV (relative change) value has any meaning. 
  



> -Original Message-
> From: [EMAIL PROTECTED] 
> [mailto:[EMAIL PROTECTED] On Behalf Of alsopb
> Sent: Tuesday, September 16, 2008 4:50 PM
> To: elecraft@mailman.qth.net
> Subject: Re: [Elecraft] K3 dbV in 2.38
> 
> 
> 
> Hi Steff,
> 
> Thanks reply.
> 
> Try this.  Set your K3 up to display dBV.  Turn your K3 off.  
> Turn the K3 on.  Look at the value.  Wait.  See if it ever 
> changes from +99.9.  It never does here.
> 
> This works:
> Have any other parameter displayed in the VFO B area.  Turn 
> rig off.  Turn it on.  That parameter does display. Then turn 
> VFO B to display dbV.  In a matter of seconds, it displays OK.
> 
> It is like the K3 doesn't know the dBV display option has 
> been selected at
> startup-- at least here.
> 
> No big problem of course.
> 
> 73 de Brian/K3KO
> 
> 
> 
> Steef PA2A wrote:
> > 
> > Brian,
> > 
> > You have to let the AFV value stabilize first, and then the 
> dBV shows 
> > the value compared to the last AFV value. Page 36 of the 
> manual shows 
> > more details.
> > 
> > 73 's Steef PA2A
> > K3 1184
> > 
> > - Original Message -
> > From: "alsopb" <[EMAIL PROTECTED]>
> > To: 
> > Sent: Tuesday, September 16, 2008 2:47 PM
> > Subject: [Elecraft] K3 dbV in 2.38
> > 
> > 
> >>
> >> When turning on the K3, the dbV readout (AGC off) reads 
> +99.9.  Tech 
> >> menu
> >> is
> >> on and other parameters one can display are OK.
> >>
> >> It doesn't change until I get impatient and start tuning around, 
> >> turning menu main on/off or switching between parameters 
> with the VFO 
> >> B knob.  It is not clear what brings it to life. ( A two 
> minute wait 
> >> alone does not do
> >> it.)
> >> After that it works properly.
> >>
> >> Anybody else seeing this?
> >>
> >> 73 de Brian/K3KO
> >>
> >>
> >> --
> >> View this message in context: 
> >> http://n2.nabble.com/K3-dbV-in-2.38-tp1092599p1092599.html
> >> Sent from the Elecraft mailing list archive at Nabble.com.
> >>
> >> ___
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> 
> -- 
> View this message in context: 
> http://n2.nabble.com/K3-dbV-in-2.38-tp1092599p1093680.html
> Sent from the Elecraft mailing list archive at Nabble.com.
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Re: [Elecraft] K3 dbV in 2.38

[alsopb]

Hi Steff,

Thanks reply.

Try this.  Set your K3 up to display dBV.  Turn your K3 off.  Turn the K3
on.  Look at the value.  Wait.  See if it ever changes from +99.9.  It never
does here.

This works:
Have any other parameter displayed in the VFO B area.  Turn rig off.  Turn
it on.  That parameter does display. Then turn VFO B to display dbV.  In a
matter of seconds, it displays OK.

It is like the K3 doesn't know the dBV display option has been selected at
startup-- at least here.

No big problem of course.

73 de Brian/K3KO



Steef PA2A wrote:
> 
> Brian,
> 
> You have to let the AFV value stabilize first, and then the dBV shows the
> value compared to the last AFV value. Page 36 of the manual shows more
> details.
> 
> 73 's Steef PA2A
> K3 1184
> 
> - Original Message - 
> From: "alsopb" <[EMAIL PROTECTED]>
> To: 
> Sent: Tuesday, September 16, 2008 2:47 PM
> Subject: [Elecraft] K3 dbV in 2.38
> 
> 
>>
>> When turning on the K3, the dbV readout (AGC off) reads +99.9.  Tech menu 
>> is
>> on and other parameters one can display are OK.
>>
>> It doesn't change until I get impatient and start tuning around, turning
>> menu main on/off or switching between parameters with the VFO B knob.  It 
>> is
>> not clear what brings it to life. ( A two minute wait alone does not do 
>> it.)
>> After that it works properly.
>>
>> Anybody else seeing this?
>>
>> 73 de Brian/K3KO
>>
>>
>> -- 
>> View this message in context: 
>> http://n2.nabble.com/K3-dbV-in-2.38-tp1092599p1092599.html
>> Sent from the Elecraft mailing list archive at Nabble.com.
>>
>> ___
>> Elecraft mailing list
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>> 
> 
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> 

-- 
View this message in context: 
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Sent from the Elecraft mailing list archive at Nabble.com.

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Re: [Elecraft] K3 dbV in 2.38

[Steef PA2A]

Brian,

You have to let the AFV value stabilize first, and then the dBV shows the
value compared to the last AFV value. Page 36 of the manual shows more
details.

73 's Steef PA2A
K3 1184

- Original Message - 
From: "alsopb" <[EMAIL PROTECTED]>

To: 
Sent: Tuesday, September 16, 2008 2:47 PM
Subject: [Elecraft] K3 dbV in 2.38




When turning on the K3, the dbV readout (AGC off) reads +99.9.  Tech menu 
is

on and other parameters one can display are OK.

It doesn't change until I get impatient and start tuning around, turning
menu main on/off or switching between parameters with the VFO B knob.  It 
is
not clear what brings it to life. ( A two minute wait alone does not do 
it.)

After that it works properly.

Anybody else seeing this?

73 de Brian/K3KO


--
View this message in context: 
http://n2.nabble.com/K3-dbV-in-2.38-tp1092599p1092599.html

Sent from the Elecraft mailing list archive at Nabble.com.

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